Population growth belongs to the one of the most crucial global problems of humankind that was recognized in the 20th century, when doubling the population size since 1960s became a clear evidence of the stunning growth. Now, the world is in the midst of its rapid population growth. The unchecked growth of the human population can affect the functioning of society and its sustainable development because of increasing the human consumption level that relates, first of all, to environmental and food insecurity. Therefore, humankind has to pay great attention to studying demographic processes.
Changes in population growth involving its acceleration and subsequent deceleration are a result of the global demographic transition process influenced by a combination of socioeconomic factors. The factors discussed in this paper include natality, international migration, population ageing, urbanization, and population density. The analysis of socioeconomic factors confirmed that unchecked population growth leads to negative consequences for sustainable development of society due to increased consumption of finite resources, disproportions in the demographic structure and in the life space, climate change and environmental problems. Also, based on the predictable nature of population growth, it helps to define the main trends of demographic transition.
Major Factors Related to Population
According to recent research, in 2012, the world population accounted for about 7 billion. Despite a decline in the population growth rate, the experts estimate further increase in population size up to between 7.5 and 10.5 billion by 2050. Changes in population growth involving its acceleration and subsequent deceleration are a result of the global demographic transition process, which is “influenced by a combination of socioeconomic factors, the behaviour of individuals and, probably to a much lesser extent, by national population policies”. The full cycle of this process, the last phase of which is estimated to be over globally by the end of the century with very low birth and death rates, is different in various regions of the world. Such unevenness divided the world demographically in two groups – countries with low fertility and high life expectancy that is typical for developed countries and countries with lower life expectancy and higher fertility that corresponds to developing ones. Besides, in poor countries from the second group the demographic processes are impacted by malnutrition, poverty, and lack of education.
This paper analyzes five major socioeconomic factors that affect population development: natality, migration, ageing, urbanization, and density.
Natality factor describes the reproductive population rate over a period of time using the terms of fertility and birth rate. The population stability is sustained at the replacement level of fertility index around 2.1 children per woman. Respectively, higher natality based on the increase of fertility and birth rates will provide a lower proportion of older people. For the last decades, the global fertility index has declined. It means lowering natality around the world that supports the experts’ prediction about the end of world population growth and completion of demographic transition by the end of the century.
At present, developed European countries along with Japan demonstrate the rapid decrease in natality, and by 2050, Japan and Germany can lose up to 14 % of their population. This trend can affect their future demographic structure and lead to negative consequences for sustainable development.
A large group of developing countries also has low natality due to below-replacement fertility rate. However, in most African countries and in some parts of Asia the demographic structure is completely different - half of their population is under 20 years of age and family size is four children per woman. For example, by 2035, Sub-Saharan Africa’s population is likely to grow by 81 %, and 15% of them will be under-nourished. Besides, the population growth in this poor region will intensify competition for resources and increase the risk of humanitarian catastrophe.
This factor influences the population development mostly in regional and national levels, but does not affect the global human population. It implies the migration of an individual from one place to another. The experts estimate the increase of migrants or people living outside their country of origin from the 175 million in 2007 up to 230 million by 2050. In the future, most migratory flows will occur “between developing countries and will increase in response to environmental pressures, extreme poverty and natural disasters”. Migration originates from uneven distribution of wealth, environmental problems, climate change, and war conflicts. Moreover, the lack of energy, water and food resources will intensify contradictions in regions where “population expansion has the greatest impact, relative to local resources and economic growth”. The striking example is the armed conflict in Europe, in Ukraine, where, according to UNHCR’ report, more than 824.000 people had to leave their home including 430.000 internally displaced persons.
Globally, in 2010, due to wars and natural disasters, the number of refugees and people displaced within their country was 43.7 million, and the half of them were children.
Ageing is another important factor that affects the population development. It arises from the interaction of natality and mortality. Higher population ageing implies proportional lowering the share of young people and increasing the share of older people. Lutz et al. consider population aging and population growth as the two sides of the same coin – demographic transition process. Countries with youngest and oldest population are shown in Table 1.
Currently, the global population with half of people below 28 years of age is not old. However, the processes of global ageing, which are not simultaneous in different regions, intensify. It clearly manifests in developed countries, where young people’s share of 15% is the lowest in the world, and in developing countries, where a third of the population will be aged over 60 by 2050. Totally, by that time, 80% of the world’s older population will live in developing countries. On the other hand, some developing countries will demonstrate the increase of young population. For example, in most African countries and in some Asian regions more than half the population is young people under 20 years of age. Another important indicator of population ageing is the extension of the life expectancy. According to the UN report, the worldwide average life length increased from 47 years of age in the early 1950s up to 68 years in 2005–2010, and will account for about 75 years by 2050.
In sum, ageing will have a future irreversible impact on the global scale through “a shrinking working population, significantly altering the balance between economically-active and -inactive members”.
This factor shows the tendency in the distribution of population between urban and rural areas. Currently, for the first time in history, the city population exceeded the rural population, and by 2035, the share of the urban population will be 60 %. Such trend is a challenge for developing countries because it implies further intensification of problems with providing basic services such as transport and waste treatment in most cities in these countries. In addition, increasing a number of urban residents means the significant growth of environmental risks. For example, Chopra and Rao argue that in India expanding urbanization declines the areas under cultivation that causes the slowdown in agricultural growth. Moreover, the increaseв rate of urbanization lessens “the need for children even as early public health measures improved life spans” .
Density of Population
This factor affects the population development through changes in the ratio between the population and its life space as an indicator of population pressure. The density of population has the tendency to rise in all major areas except Europe and thereby strengthens disproportions in the life space in different part of the world. For example, by 2100, in Australia an average population density will grow from 3 to 3.6 of citizens per sq.km., while in Micronesia - from 145 up to 540 citizens per sq. km.. The most densely populated part of the world is Asia with the highest growth rate of density, which will reach 165 persons per sq.km. by 2050. Apart from Macao and Hong Kong in China and Singapore, Bangladesh is likely to be the most densely populated country with 1.764 people per sq.km..
Finally, the increase of population density intensifies environmental problems and uneven wealth distribution that promotes in turn international migration affecting proportional population development.
Population growth belongs to one of the most crucial problems of humankind. The analysis of socioeconomic factors that affect the demographic development leads to a conclusion that unchecked population growth provides negative consequences for sustainable development of society due to increased consumption of finite resources, disproportions in the demographic structure and in the life space, climate change and environmental problems. In addition, it allows defining the main trends of world demographic development:
- While population development of the developed countries is characterized by the decrease of growth rate and the increase of population ageing, the highest rate of population growth is typical for the poorest countries that lack capabilities to meet growing demands and provide equal opportunities for their population. It creates the huge disproportions in the age structure of developing and developed countries that deteriorate the global sustainable development;
- Mostly, immigration will maintain the population growth in developed countries;
- Urbanization becomes a challenge mostly for the less developed regions that have a lack of capability to meet the growing needs;
- Increasing the class of the poor on account of refugees as a large part of migrants will intensify the problems of social development, especially, in developing countries;
- Uneven increasing of population density will worsen environmental problems and wealth distribution that will affect the proportional population development.
Questions and Answers
How important is writing about population and why?
The rapid growth of the population can affect the functioning of society and its sustainable development because of increasing the human consumption level related, first of all, to environmental and food insecurity. Therefore, humankind has to pay great attention to demographic processes in respect of maintaining the stable level of economic growth, reasonable consumption of natural resources and saving of environment. Accordingly, writing about population is important because it helps improve understanding of demographic information that is the basis for the analysis of social development and qualified decisions in the field of economy, education, employment, social affairs, etc.
What region is most impacted by the issue?
Most of the population increase will be in Asia and Africa, which will have to respond to the lack of resources required to provide their stable development. A most problematic region in respect of population growth in these parts of the world is Sub-Saharan Africa, where population is expected to rise by 81% by 2035, and 15% of them will be under-nourished. Such situation will intensify competition for resources and increase the risk of humanitarian catastrophe in the region.
How would a regional perspective on population vary from a national or global one?
Although there is a decline in the global population growth rate, by 2050 the size of the world population will increase by about 2.5 billion or 37% compared with 2011. Africa will demonstrate more than twice increase – the highest increase among regions; America’s region, including Northern America, Latin America and Caribbean, will participate with a 30% increase; the population of Asia will increase by 1.3 times; in Europe the population size will not change; the countries of Oceania will demonstrate 70% or 1.7 times increase. Smaller regions will have a different development. For example, increase in Western and Eastern Africa is expected to be 2.5 times or 153% (Niger- 3.4 times or 245% increase; Zambia- 3.3 (230%); Uganda- 3.1 or 200%). The most populous region will be Asia, and the most populous country- India followed by China and Nigeria. As a corollary, while population development of the developed countries is characterized by the decrease of growth rate and the increased population ageing, the highest rate of population growth is in the poorest countries that have a lack of capability to meet growing demands and create equal opportunities for their population.
What is the most interesting, surprising, encouraging, or worrisome thing you learned about population?
I have found that the most interesting thing related to population development is a demographic window – the period of countries demographic development characterized by having the share of young population under the age of 15 years old that does not exceed 30% of the whole population and the share of older people over 65 years that does not exceed 15%. It means that the people of most productive age of 30-40 years are the prevalent part of society. While Europe took an opportunity of its demographic window that appeared before 1950s, Africa is likely to have a demographic window by 2045.